MARY Shelley deserves all the love and affection being poured in her direction to mark the 200th anniversary of her masterpiece, Frankenstein – and this film attempts to bring her remarkable story to the mainstream.

But annoyingly, in doing so, it lacks revolu­tionary spirit – which means it doesn’t feel like the film genuinely “gets” Mary, or her husband, Percy Bysshe Shelley. Sadly it goes along a well-worn groove in considering the pair. Oh how refreshing it would be if we could have a film that avoids the clichés, the accepted lies and the propaganda spouted against them because they said no to the status quo and dared dream of better days for all.

We meet the young Mary (Elle Fanning) as she writes ghost stories under the disapproving eye of her stepmother and the more benevolent guidance of her father, the philosopher William Godwin.

We’re given the back story – the death of her mother, the feminist and philosopher Mary Wollstonecraft, days after giving birth to Mary – and then we are taken to where she first met the poet Shelley, and how they fell in love, faced money troubles (though Shelley being cut off by his family for his politics is brushed over) to their time on the Continent and the inspirations for Frankenstein.

While a celebration of Mary’s extraordinary life, and anything that brings her work and that of her mother to the contemporary eye must be applauded, there is still something rotten here.

It’s not the scene after scene of shouty setpieces, or Lord Byron’s (Tom Sturridge) dandy shtick that grates. What most irritates is yet another portrayal of Shelley as a fairly loathsome character. That nearly 200 years after his death the same misconceptions and propaganda about his character can still be peddled is a source of sadness. Douglas Booth’s version isn’t as bad as others – Shelley has been the subject of centuries of lies – but he is still seen as some kind of uncaring free love philanderer, who would take the credit for Mary’s work if he could.

Why is this still the case? Read Paul Foot’s masterful critique, Red Shelley, and the story of the pair is illuminated. George Orwell wrote: “The more I see, the more I doubt whether people ever really make aesthetic judgements at all. Everything is judged on political grounds which are then given an aesthetic disguise. When, for instance, Eliot can’t see anything good in Shelley or bad in Kipling, the real underlying reason must be that one is a radical and the other is a conservative of sorts.”

The portrayal of Shelley as some feeble fop instead of the restless agitator is a trick those who don’t like his views have been playing on us since he was first published.

Mary wrote: “My husband was from the first very anxious that I should prove myself worthy of my parentage and enrol myself on the page of fame.

“He desired I should write… at first I thought of but a few pages – of a short tale, but Shelley urged me to develop the idea at greater length… but for his incitement it would never have taken the form in which it was presented to the outside world.”

Mary was a brilliant writer and free thinker, and what makes her more remarkable was the period she came from.

This biopic doesn’t quite celebrate her enough – nor her muse. It is as if we still have not been able to truly recognise her greatness, nor his, or how they could dovetail together.